This invention relates to apparatus for loading cylindrical inserts in a metal mold of a die cast machine and which is especially suitable for use in a die cast machine designed to manufacture cylinder blocks of V-type internal combustion engines.
Where the cylinder block of an engine of a motor car and the like is manufactured by die casting molten aluminum, cylindrical inserts made of cast iron and later acting as cylinder liners are loaded in the metal mold of a die cast machine, and then molten aluminum is cast such that the cylindrical inserts and cast aluminum become integral. To accomplish this, it is necessary to use an insert loading apparatus capable of accurately supplying the cylindrical inserts to predetermined positions of the metal mold.
Such cylindrical insert loading apparatus must satisfy the following requirements. More particularly, it is required than an insert transfer unit which is reciprocated between an insert supply furnace and the metal mold of the die cast machine should be operated rapidly and smoothly, that the insert transfer unit should be correctly positioned at insert receiving positions of the metal mold, and that a plurality of inserts can be loaded simultaneously. To this end, the pitch between adjoining insert receiving positions should be equal to that to adjoining insert holders of the insert transfer unit.
In a cylinder block of an engine in which cylinders are arranged on a straight line or in a horizontally opposing configuration, it is only necessary to match the pitches in a plane perpendicular to the axis of the die cast machine, but in a case where the directions of loading the cylinder liners cross with each other as in the cylinder block of a V-type engine, in addition to the pitch matching described above, it is also necessary to correctly position the insert transfer unit with respect to the insert receiving positions in the axial direction of the die cast machine. However, since the separation of the movable metal mold from the stationary metal mold is determined by the operating timing of a limit switch, the movable metal mold stops with an error of 2 to 3 mm and the positioning in the axial direction becomes extremely difficult. Accordingly, it has been strongly desired to have improved insert loading apparatus capable of overcoming such difficulties.